Caught in the act: Implications for the increasing abundance of mafic enclaves during the eruption of the Soufriere Hills Volcano, Montserrat

An exceptional opportunity to sample several large blocks sourced from the same region of the growing Soufrière Hills lava dome has documented a significant increase in the presence of mafic enclaves in the host andesite during the course of a long-lived eruptive episode with several phases. In 1997 (Phase I) mafic inclusions comprised ~1 volume percent of erupted material; in 2007 (Phase III) deposits their volumetric abundance increased to 5–7 percent. A broader range of geochemically distinctive types occurs amongst the 2007 enclaves. Crystal-poor enclaves generally have the least evolved (basaltic) compositions; porphyritic enclaves represent compositions intermediate between basaltic and andesitic compositions. The absence of porphyritic enclaves prior to Phase III magmatism at Soufrière Hills Volcano suggests that a mixing event occurred during the course of the current eruptive episode, providing direct evidence consistent with geophysical observations that the system is continuously re-invigorated from depth

Making the most of the Mogi model: Size matters

Magma movements are almost universally associated with volcanic deformation. The Mogi (1958) and McTigue (1987) models link observed surface displacements to behaviour within inaccessible magmatic plumbing systems. Mogi and McTigue models are well-used due to their computational simplicity and ease of application, but both models are limited by their assumptions about the deformation source and its embedding domain. Domain assumptions, including elasticity, homogeneity, and flat topography, have been previously described and corrected for. Whilst recognising the limits of these models, their frequent use in the literature requires an objective assessment of their utility against more sophisticated Finite Element (FE) models, their operational limits (radius-to-depth ratio, ε) and their relative merits in the light of limited field data. Here, we relax the source assumption of a small ε. We simulate volcanic deformation using Mogi, McTigue and FE models - the latter unrestricted by ε - to validate the maximum ε for which the analytical models can be applied, and to compare analytical and FE interpretations of deformation data from Kīlauea Volcano, Hawai'i. We find that analytical and FE models correspond for deformation sources with a range of ε that is wider than previously suggested limits. The differences between simulated surface displacements (forward modelling) and estimated deformation source parameters (inverse modelling) are less than 5% when ε < 0.37 (Mogi) or ε < 0.59 (McTigue). Misfits between analytical and FE models depend on whether radial or vertical displacements are considered simultaneously or independently, and on the values of source radius and depth - not only their ratio, as was assumed previously. There is little or no difference between best-fitting source parameters inferred using Mogi, McTigue and FE models at Kīlauea Volcano, despite the high ε of the system geometry, but sometimes poor correspondences between model results and GNSS observations. Our results demonstrate that Mogi and McTigue models can be applied to volcanoes with a wider range of magma reservoir radii and depths than was hitherto supposed, but previously-established corrections for domain simplifications are necessary to accurately interpret volcanic deformation

Development and fabrication of a Bi-2223 racetrack coil for generator applications

The development and fabrication of a layer-wound, epoxy-impregnated Bi-2223 high-temperature superconducting (HTS) racetrack coil which generates 40,000 ampere-turns of magnetomotive force (MMF) at 25 K is described. The coil was wound using Ag-sheathed Bi-2223 tape conductor laminated with copper foils for strength enhancement and insulated using a paper-wrap method. After epoxy impregnation, the coil was tested over a range of 16--25 K in a vacuum dewar using a closed-cycle helium refrigeration system. Descriptions of the tape lamination and insulation processing, the coil winding and impregnation, and the experimental test setup are given

A systematic genome-wide analysis of zebrafish protein-coding gene function

Since the publication of the human reference genome, the identities of specific genes associated with human diseases are being discovered at a rapid rate. A central problem is that the biological activity of these genes is often unclear. Detailed investigations in model vertebrate organisms, typically mice, have been essential for understanding the activities of many orthologues of these disease-associated genes. Although gene-targeting approaches1, 2, 3 and phenotype analysis have led to a detailed understanding of nearly 6,000 protein-coding genes3, 4, this number falls considerably short of the more than 22,000 mouse protein-coding genes5. Similarly, in zebrafish genetics, one-by-one gene studies using positional cloning6, insertional mutagenesis7, 8, 9, antisense morpholino oligonucleotides10, targeted re-sequencing11, 12, 13, and zinc finger and TAL endonucleases14, 15, 16, 17 have made substantial contributions to our understanding of the biological activity of vertebrate genes, but again the number of genes studied falls well short of the more than 26,000 zebrafish protein-coding genes18. Importantly, for both mice and zebrafish, none of these strategies are particularly suited to the rapid generation of knockouts in thousands of genes and the assessment of their biological activity. Here we describe an active project that aims to identify and phenotype the disruptive mutations in every zebrafish protein-coding gene, using a well-annotated zebrafish reference genome sequence18, 19, high-throughput sequencing and efficient chemical mutagenesis. So far we have identified potentially disruptive mutations in more than 38% of all known zebrafish protein-coding genes. We have developed a multi-allelic phenotyping scheme to efficiently assess the effects of each allele during embryogenesis and have analysed the phenotypic consequences of over 1,000 alleles. All mutant alleles and data are available to the community and our phenotyping scheme is adaptable to phenotypic analysis beyond embryogenesis

The use of cessation assistance among smokers from China: Findings from the ITC China Survey

<p>Abstract</p> <p>Background</p> <p>Stop smoking medications significantly increase the likelihood of smoking cessation. However, there are no population-based studies of stop-smoking medication use in China, the largest tobacco market in the world. This study examined stop-smoking medication use and its association with quitting behavior among a population-based sample of Chinese smokers.</p> <p>Methods</p> <p>Face-to-face interviews were conducted with 4,627 smokers from six cities in the ITC China cohort survey. Longitudinal analyses were conducted using Wave 1 (April to August, 2006) and Wave 2 (November 2007 to January 2008).</p> <p>Results</p> <p>Approximately 26% of smokers had attempted to quit between Waves 1 and 2, and 6% were abstinent at 18-month follow-up. Only 5.8% of those attempting to quit reported NRT use and NRT was associated with lower odds of abstinence at Wave 2 (OR = 0.11; 95%CI = 0.03-0.46). Visiting a doctor/health professional was associated with greater attempts to quit smoking (OR = 1.60 and 2.78; 95%CI = 1.22-2.10 and 2.21-3.49 respectively) and being abstinent (OR = 1.77 and 1.85; 95%CI = 1.18-2.66 and 1.13-3.04 respectively) at 18-month follow-up relative to the smokers who did not visit doctor/health professional.</p> <p>Conclusions</p> <p>The use of formal help for smoking cessation is low in China. There is an urgent need to explore the use and effectiveness of stop-smoking medications in China and in other non-Western markets.</p

Personality Predicts Mortality Risk: An Integrative Data Analysis of 15 International Longitudinal Studies

This study examined the Big Five personality traits as predictors of mortality risk, and smoking as a mediator of that association. Replication was built into the fabric of our design: we used a Coordinated Analysis with 15 international datasets, representing 44,094 participants. We found that high neuroticism and low conscientiousness, extraversion, and agreeableness were consistent predictors of mortality across studies. Smoking had a small mediating effect for neuroticism. Country and baseline age explained variation in effects: studies with older baseline age showed a pattern of protective effects (HR<1.00) for openness, and U.S. studies showed a pattern of protective effects for extraversion. This study demonstrated coordinated analysis as a powerful approach to enhance replicability and reproducibility, especially for aging-related longitudinal research.Funding support for this project was provided by the National Institute on Aging: P01-AG043362 (Integrative Analysis of Longitudinal Studies of Aging (IALSA), [Scott M. Hofer (PI)]), and Daniel K. Mroczek (CoInvestigator and Project Leader of the IALSA Personality & Health Project, as well as R01-AG018436 [Personality & Well-Being Trajectories in Adulthood, Daniel K. Mroczek, PI])

What can Olympus Mons tell us about the Martian lithosphere?

Under gravitational loading, a volcanic edifice deforms, and the underlying lithosphere downflexes. This has been observed on Earth, but is equally true on other planets. We use finite element models to simulate this gravity-driven deformation at Olympus Mons on Mars. Eleven model parameters, including the geometry and material properties of the edifice, lithosphere and underlying asthenosphere, are varied to establish which parameters have the greatest effect on deformation. Values for parameters that affect deformation at Olympus Mons, Mars, are constrained by minimising misfit between modelled and observed measurements of edifice height, edifice radius, and flexural moat width. Our inferred value for the Young's modulus of the Martian lithosphere, 17.8 GPa, is significantly lower than values used previously, suggesting that the Martian lithosphere is more porous than generally assumed. The best-fitting values for other parameters: edifice density (2111 – 2389 kg.m –3) and lithosphere thickness (83.3 km) are within ranges proposed hitherto. The best-fitting values of model parameters are interdependent; a decrease in lithosphere Young's modulus must be accompanied by a decrease in edifice density and/or an increase in lithosphere thickness. Our results identify the parameters that should be considered within all models of gravity-driven volcano deformation; highlight the importance of the often-overlooked Young's modulus; and provide further constraints on the properties of the Martian lithosphere, namely its porosity, which have implications for the transport and storage of fluid throughout Mars' history

Home-based care of low-risk febrile neutropenia in children-an implementation study in a tertiary paediatric hospital

BACKGROUND: Home-based management of low-risk febrile neutropenia (FN) is safe, improves quality of life and reduces healthcare expenditure. A formal low-risk paediatric program has not been implemented in Australia. We aimed to describe the implementation process and evaluate the clinical impact. METHOD: This prospective study incorporated three phases: implementation, intervention and evaluation. A low-risk FN implementation toolkit was developed, including a care-pathway, patient information, home-based assessment and educational resources. The program had executive-level endorsement, a multidisciplinary committee and a nurse specialist. Children with cancer and low-risk FN were eligible to be transferred home with a nurse visiting daily after an overnight period of observation for intravenous antibiotics. Low-risk patients were identified using a validated decision rule, and suitability for home-based care was determined using disease, chemotherapy and patient-level criteria. Plan-Do-Study-Act methodology was used to evaluate clinical impact and safety. RESULTS: Over 18 months, 292 children with FN were screened: 132 (45%) were low-risk and 63 (22%) were transferred to home-based care. Compared with pre-implementation there was a significant reduction in in-hospital median LOS (4.0 to 1.5 days, p < 0.001) and 291 in-hospital bed days were saved. Eight (13%) patients needed readmission and there were no adverse outcomes. A key barrier was timely screening of all patients and program improvements, including utilising the electronic medical record for patient identification, are planned. CONCLUSION: This program significantly reduces in-hospital LOS for children with low-risk FN. Ongoing evaluation will inform sustainability, identify areas for improvement and support national scale-up of the program

Finishing the euchromatic sequence of the human genome

The sequence of the human genome encodes the genetic instructions for human physiology, as well as rich information about human evolution. In 2001, the International Human Genome Sequencing Consortium reported a draft sequence of the euchromatic portion of the human genome. Since then, the international collaboration has worked to convert this draft into a genome sequence with high accuracy and nearly complete coverage. Here, we report the result of this finishing process. The current genome sequence (Build 35) contains 2.85 billion nucleotides interrupted by only 341 gaps. It covers ∼99% of the euchromatic genome and is accurate to an error rate of ∼1 event per 100,000 bases. Many of the remaining euchromatic gaps are associated with segmental duplications and will require focused work with new methods. The near-complete sequence, the first for a vertebrate, greatly improves the precision of biological analyses of the human genome including studies of gene number, birth and death. Notably, the human enome seems to encode only 20,000-25,000 protein-coding genes. The genome sequence reported here should serve as a firm foundation for biomedical research in the decades ahead